You'll wake up in a room and James (no, you shouldn't know who he is) will come to get you. He'll take you down the hall to meet up with Admiral Anderson who will fill you in. Admiral Anderson will take you to the Command Council because they have some questions and you're going to be the only one with any answers. After all hell breaks loose, follow Anderson out of the "window." He'll travel left, follow him.
You'll come to a point where Husks will start to scale a building. You can shoot them as they climb or at the top as they run away. Kill a few (or run low on ammo) and you'll be sent to go down the nearby ladder. Empty your weapon and then you will have to melee the Husks to death. Go up to them and rapidly press the melee button to execute multiple consecutive melee attacks. After you kill them, the building next to you will explode, allowing you to enter the wreckage. Go inside. In the first room will be a Med Kit. Go into the next room and kill the husk stuck in the door with a heavy melee attack (executed by holding the melee button).
When you regain control after the cutscene, follow Anderson outside. Far in the distance, a dreadnought class ship will explode (in atmosphere!) causing you some problems. Follow the line of wreckage and you'll come across a couple of soldiers, one of which is wounded. You'll encounter your first new enemy here called a Cannibal. Cannibals were originally Batarians that have been horrendously altered by the reapers. They are capable of using guns and grenades. They can also eat the corpses of Husks and other Cannibals (where they get their name) which will restore their health and add a layer of armor that needs to be shot off to damage them. These enemies can't get to you so you can make quick work of them. Kill them and then cross your new bridge to the other side. Turn left and make your way up to the higher ground. Watch out for the Med Kit on the right as you go.
|If you're short on kills for the Veteran Achievement/Trophy then the spot where you found the medic and the wounded soldier is a good spot. You'll start the battle in cover but if you step out (put the difficulty onNarrative) then the Cannibals will spawn indefinitely. The ammo just in front and to the right of you will also continually spawn allowing you to shoot and use powers constantly. While it seems boring, you can get as many kills in an hour here as you can in half of a playthrough.|
You'll come to another encounter with Cannibals. This time it's a real fight so be careful. In particular, they will start to make use of their grenades which will force you to leave cover and brave their bullets. Remember that if you have imported a character, you should have full access to your abilities from Mass Effect 2 so use them to your advantage here. You have a decent amount of running up space so take your time and kill them. Once they are dead, head up to where they were and go left. Drop down and head to the far side of the wreckage.As you get close to the end, you will find an M-8 Avenger on the ground next to the Radio. Activate the radio and then you will be attacked. The goal for this encounter is to actually run out of ammo. This is the only way to trigger your rescue so use bullets for most kills and only use powers sparingly to keep yourself alive. Once you are low or out of ammo, your ride will arrive.
|Before you leave Earth, make sure that you set your difficulty to whatever you would like it to be. Once you leave Earth, changing it can affect achievements.|
|It is possible to actually just shoot your weapon backwards from behind cover (so that you don't stand up) and run out of ammo to finish this almost instantly. But where's the fun in that? It is also possible to use strictly powers and after a certain amount of time, the battle will end. Complete inaction (aside from moving) will not complete this battle however.|